Although indolent for long periods, MGUS carries a risk of progression to malignant conditions, including multiple myeloma (MM; non-IgG or IgA), Waldenström macroglobulinemia (IgM type), AL amyloidosis (IgM type), or other lymphoproliferative disorders, at an approximate rate of 1% per year [11]. The gene discussed is CD79A; the disease is lymphoproliferative syndrome.